In-tank filters provided for filtering fuel supplied to the inlet of a fuel pump face tight spatial restrictions and must thus be small in size, yet provide a large filter surface for ensuring a continuous functionality without clogging. These demands have resulted in filters that are bent to be arranged along the pump surface, or to form filter layers arranged parallel to each other. Filters arranged along the surface of the pump must be retained on the pump, which requires additional labor steps. In contrast, filters folded onto themselves to form layers at an acute angle or parallel to each other can be easily preassembled into their folded shape, provided that the filter possesses a retention feature that prevents unfolding of the filter prior to installation. Such retention features typically require that additional components are affixed to the filter, increasing the cost of the filter and possibly reducing the filtration area and capability of the filter. The additional components include a plastic zip tie or other plastic wrap that would encircle the folded portions of the filter to hold the folded position.